Process of preparing fuel composition.



UNITED ST TES Patented May 26, 1903.

PATENT OFFICE.

OSKAR FRANCKE, OF MUHLHAUSEN, GERMANY, ASSIGN OR TO MARTIN HEBERLEIN, OFEISENACH, GERMANY.

PROCESS OF PREPARING FUEL COMPOSITION.

SPECIFICATION forming part of Letters Patent N 0. 729,321, dated May 26,1903.

Application filed October 31, 1901.

T0 aZZ whom it may concern.-

Beit known that I, OSKAR FRANOKE, man ufacturer, a subject of the Kingof Prussia, German Emperor, residing at Miihlhausen i. Th., in theKingdom of Prussia, German Empire, have invented certain new and usefulImprovements in Processes of Preparing Fuel Compositions, of which thefollowing is a specification.

The present invention relates to a method of increasing the heatingpowerof combustibles in general. I

The improved method consists, mainly, in adding to the combustiblesother substances in a finely-divided condition formingnitroglycerin-like compounds, from which on com-- bustion taking placegases of intense heating power are developed.

The invention consists, further, in adding substances which when burnedat an intense heat produce Dowson-like gases. Owing to this treatmentthe combustibles may be easily ignited and produce on burningan intenseand lasting heat. The method, therefore, is especially adapted forenriching combustibles of inferior value, such as poor brown coal, peat,waste peat, leaves, sawdust, coal-slime, peatslime, and poor coalandfuel in general, such fuel being generally very difficult to igniteand developing but small heating poweron being burned. By the abovetreatment the combustibles are enriched, so as to become easilyinflammable and to give a considerably-increased heating power. Themethod, however, is also applicable to fuel of comparatively highheating power-such 'as mineral coal, good brown coal, or the likeas theheating power and the intlammability of such fuel also are considerablyincreased by the above treatment.

The method is based on covering or impregnating the fuel (whichpreferably is treated after having been suitably reduced) with a layerof suchmatters, which form a nitroglycerin-like compound spread in afinely-divided state over the fuel. By this means the inflammability ofthe fuel is considerably increased, superheated steam in afinely-divided condition is produced in the fuel, the combustion takingplace, so that the fuel,

which under the influence of the heat pr0- erial No. 80.707. (Nospecimens.)

duced from the nitroglycerin-like compounds, glows and produces aDowson-like gas,which burns as it is produced by the heat of the burninggases of the nitroglycerin-like compounds. In order to provide the fuelwith such a water-containing nitroglycerin-like coating, the followingmethod is employed:

The combustiblefor instance, coal, coaldust, peat-rubble, leaves,sawdust, coal-mud, or peat-mud-with a total weight of, say,

twenty-five kilograms is first intimatelymixed in a suitably-reducedstate with twenty-five kilograms of a suitable calcium salt, such ascalcium sulfate, and also with a little ash,

pound is not a pure nitroglycerin, as for the formation of the lattersulfuric acid is required. The mixture of fuel and ingredients isfinally slightly compressed and dried in the air, whereupon it is readyfor use. The abundant supply of water causes the nitric acid in theglycerin to be finely distributed throughout the whole mass, water beingalso contained in the form of very fine particles in the interior of theartificial fuel produced as above. The sulfate of lime binds or inclosesthe coal-component parts and the nitroglycerin-like compounds and servesin its glowing condition as a conductor of heat. The gases developedfrom these compounds then produce an intense local combustion. By thismeans the coal particles contained in the interior of the fuel are cokedand the inclosed water particles are changed into steam and superheated.They combine with the glowing coked coal to form a Dowson-like gas,which produces an energetic combustion and also enables a very hightemperature to be obtained. The gases produced from thenitroglycerin-like compound and the Dowson gas,

produced by the coking of the coal and the presence of the water,produce on burning a considerable heat, and consequently increase theheating power of the fuel. In this way on combustion taking placenitroglycerinlike, but not pure nitroglycerin, compounds are obtained.The development of gases from such nitroglycerin-like compounds, as wellas the development of the Dowson gas, takes place only in the heatedportion of the fuel. These gases burn in statu nascendi and in this waygive up their heating energy. Hydrocarbons such as resins, oils, petrol,waste naphtha may be added to the carbon, if desired, without departingfrom the spirit of the invention.

From the foregoing description it will be seen that the presentinvention is especially adapted for enriching poor fuelsuch as peat,peat Waste, sawdust, leaves, &c. When using peat as fuel, the new methodhas the advantage that the peat need not be dried, as according to theinvention Water is added to the fuel, which in carrying out the processis bound and becomes free only on combustion taking place.

Artificial fuel obtained by the method according to the presentinvention is readily inflammable and produces considerable heat onburning. It might be added to other combustibles of inferior valueforinstance, to poor brown coal (the whole mixture being used instead ofgood mineral coal)in order to obtain an energetic combustion; also, goodcoal may be enriched as regards heating power and inflammability bymeans of the described process, such a coal giving aconsiderably-increased heating power per unit of volume. This may be ofspecial importance in cases when an intense production of heat isintended to take place in a limited space or when the room for storingfuel is very restricted-as, for instance, in vessels, en-

gines, or the like. The increase of heating power' of the fuel is alsoof great importance in metallurgy and in the metal industries.

Coal treated according to the method described burns with a whiteluminous flame, almost without production of smoke, and very uniformly.The ashes are white and owing to the intense development of gases breakup easily, so that they can be removed readily from the grate. The ashescontinue in a white glowing condition until the gases produced from theglycerin compound and the coal and the Dowson-like gases are totallyconsumed.

Fuel treated according to the method described may be, if desired,formed into briquets, cubes, or the like and then dried.

I claim 1. The method described, consistingin mixing intimately areduced combustible with calcium sulfate, then applying dilute nitric'acid and dilute glycerin so as to inclose or coat the combustible withnitroglycerin-like substance and Water, and finally forming the fuelinto desired shapes and drying the same, substantially as described.

2. The method described, consisting in mixing intimately a reducedcombustible with calcium sulfate, then applying dilute nitric acid anddilute glycerin so as to inclose or coat the combustible with anitroglycerinlike substance and water, and adding liquid hydrocarbon,such as residues of resin, substantially as described.

In testimony whereof I have hereunto set my hand in presence of twosubscribing witnesses.

OSKAR FRANCKE.

Witnesses WILHELM BINDEWALD, MAX MEYER.

